What's the best way to share a wallet? Do I have to create the bitcoin.exe -server on a single computer, then have all of the other computers on the LAN connect through it? How would I go about setting that up with poclbm? Would I just use something like -host 192.168.1.3? Can I have two bitcoin.exe's running on two separate computers and somehow use the same wallet.data?

Right now, I'm doing shared pooling through deepbit anyway, but I want to know all of my options, so I'd like to know how to properly set this up.

0.3.21 contains a patch that makes the client monitor the network for transactions both from and to its own keys. In theory, you can share a wallet.dat file between two systems, but you need to be very careful. The wallet.dat file contains 100 future keys, but this does mean that if you do transactions from both nodes, they will start to diverge, and after 100 transactions, they will start using different keys. Also, if you have done a transaction from one node, unknown by the others, there is a chance that you will do a double spend, and have a wallet with invalid change transactions in it (possibly leading to more transactions that never get accepted).

I think a partial solution for the divergence is to identify one copy of the wallet as a primary, and periodically (before the 100 keys in the pool are used up) overwrite all other copies from the primary. This is kind of what I do with my Bitcoin-on-USB installation.